The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: hdawson on 15.09. 2019 11:12

Title: Speedo issues
Post by: hdawson on 15.09. 2019 11:12
After recently fixing my gearbox problems things are going great.
Had a nice run yesterday but my speedo seems to be running twice as fast as usual
Because gearbox inner and outer were removed dozens of times between short tests I am unaware when this may have changed.
What could I have possibly done to cause this or have I lost my mind?
Cheers, Hadrian.

Title: Re: Speedo issues
Post by: Swarfcut on 18.09. 2019 20:41
Hi Hadrian..As no other bugger has chipped in, I suppose they are all as baffled as me. Assuming the speedo is driven off the gearbox, then the only variables are the gear clusters selected, the speedo drive gear or the speedo head. So if you are sure the gears within the box are the same, the fault must be in the speedo head.

 Does twice as fast mean actual 30mph recorded as 60mph, or 5 miles recorded as 10? Or both? Chronometric or Indian Cheapo?

Swarfy.
Title: Re: Speedo issues
Post by: berger on 18.09. 2019 21:40
make sure you have the correct cable to match the speedo, I am sure this has been covered on the forum but a magnetic speedo drive cable has 9/16 of drive protruding that fits in the speedo. a chrono cable has 7/16 protruding where it fits in the speedo. years ago I learnt the hard way by using a crap made cable that went too far into the rev counter putting pressure on things and making it whizz round then breaking the CABLE!! and the tacho *eek* very expensive  *bash*
Title: Re: Speedo issues
Post by: hdawson on 19.09. 2019 12:12
Thanks for the replies.
Another BSA mystery  *smile*
I'll never lose the enjoyment of the weird stuff that my bikes throw up.
Cheers,  Hadrian.